//Copyright notice:
// The following software is derived from the RSA Data
// Security, Inc. MD5 Message-Digest Algorithm.  Accordingly,
// the following copyright notice is reproduced, and applies to
// such parts of this file which are copied from RSA's source code.
// All other parts of the file are copyright 1998 ABKGroup and
// the Regents of the University of California.


/* Copyright (C) 1991-2, RSA Data Security, Inc. Created 1991. All
rights reserved.

License to copy and use this software is granted provided that it
is identified as the "RSA Data Security, Inc. MD5 Message-Digest
Algorithm" in all material mentioning or referencing this software
or this function.

License is also granted to make and use derivative works provided
that such works are identified as "derived from the RSA Data
Security, Inc. MD5 Message-Digest Algorithm" in all material
mentioning or referencing the derived work.

RSA Data Security, Inc. makes no representations concerning either
the merchantability of this software or the suitability of this
software for any particular purpose. It is provided "as is"
without express or implied warranty of any kind.

These notices must be retained in any copies of any part of this
documentation and/or software.

*/

#ifdef _MSC_VER
#pragma warning(disable:4786)
#endif


#include <vector>
#include "../abkMD5.h"
#define S11 7
#define S12 12
#define S13 17
#define S14 22
#define S21 5
#define S22 9
#define S23 14
#define S24 20
#define S31 4
#define S32 11
#define S33 16
#define S34 23
#define S41 6
#define S42 10
#define S43 15
#define S44 21
static unsigned char PADDING[64] = {
     0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 
};

/* F, G, H and I are basic MD5 functions.

      */

#define F(x, y, z) (((x) & (y)) | ((~x) & (z)))
#define G(x, y, z) (((x) & (z)) | ((y) & (~z)))
#define H(x, y, z) ((x) ^ (y) ^ (z))
#define I(x, y, z) ((y) ^ ((x) | (~z)))

/* ROTATE_LEFT rotates x left n bits.

      */

#define ROTATE_LEFT(x, n) (((x) << (n)) | ((x) >> (32-(n))))

/* FF, GG, HH, and II transformations for rounds 1, 2, 3, and 4.
Rotation is separate from addition to prevent recomputation.

      */

#define FF(a, b, c, d, x, s, ac) { \
     (a) += F ((b), (c), (d)) + (x) + (unsigned)(ac); \
     (a) = ROTATE_LEFT ((a), (s)); \
     (a) += (b); \
     } 
#define GG(a, b, c, d, x, s, ac) { \
     (a) += G ((b), (c), (d)) + (x) + (unsigned)(ac); \
     (a) = ROTATE_LEFT ((a), (s)); \
     (a) += (b); \
     } 
#define HH(a, b, c, d, x, s, ac) { \
     (a) += H ((b), (c), (d)) + (x) + (unsigned)(ac); \
     (a) = ROTATE_LEFT ((a), (s)); \
     (a) += (b); \
     } 
#define II(a, b, c, d, x, s, ac) { \
     (a) += I ((b), (c), (d)) + (x) + (unsigned)(ac); \
     (a) = ROTATE_LEFT ((a), (s)); \
     (a) += (b); \
     } 

MD5::MD5():_isFinalized(false)
    {
    _initState();
    }


MD5::MD5(const char *input, unsigned length, bool lastUpdate):_isFinalized(false)
    {
    _initState();
    update(input,length,lastUpdate);
    }

MD5::MD5(const char *input, bool lastUpdate):_isFinalized(false)
    {
    _initState();
    update(input,lastUpdate);
    }

void MD5::_initState()
    {
    _state[0] = 0x67452301;
    _state[1] = 0xefcdab89;
    _state[2] = 0x98badcfe;
    _state[3] = 0x10325476;
    _count[0]=0;
    _count[1]=0;
    }


void MD5::encode (unsigned char *output, const unsigned *input, unsigned len)
    {
    unsigned int i, j; 
    
    for (i = 0, j = 0; j < len; i++, j += 4) 
        { 
        output[j] = (unsigned char)(input[i] & 0xff); 
        output[j+1] = (unsigned char)((input[i] >> 8) & 0xff); 
        output[j+2] = (unsigned char)((input[i] >> 16) & 0xff); 
        output[j+3] = (unsigned char)((input[i] >> 24) & 0xff); 
        } 
    }

void MD5::decode (unsigned *output, const unsigned char *input, unsigned len)
    {
    unsigned int i, j; 
    
    for (i = 0, j = 0; j < len; i++, j += 4) 
        output[i] = ((unsigned)input[j]) | 
        (((unsigned)input[j+1]) << 8) | 
        (((unsigned)input[j+2]) << 16) | 
        (((unsigned)input[j+3]) << 24); 
    }

void MD5::update(const char *input, bool lastUpdate)
    {
    abkfatal(!_isFinalized,"Can't update MD5 after final update");
    _update((const unsigned char*)input,strlen(input));
    if (lastUpdate)
        _finalize();
    }

void MD5::update(const char *input,unsigned inputLen, bool lastUpdate)
    {
    abkfatal(!_isFinalized,"Can't update MD5 after final update");
    _update((const unsigned char*)input,inputLen);
    if (lastUpdate)
        _finalize();
    }

void MD5::finalize()
    {
    abkfatal(!_isFinalized,"Can't finalize twice");
    _finalize();
    }

void MD5::_update(const unsigned char *input,unsigned inputLen)
    {
    unsigned  i, index, partLen; 
    
    /* Compute number of bytes mod 64 */
    index = (unsigned)((_count[0] >> 3) & 0x3F);
    
    /* Update number of bits */
    if ((_count[0] += ((unsigned)inputLen << 3))
        < ((unsigned)inputLen << 3))
        _count[1]++;
    _count[1] += ((unsigned)inputLen >> 29);
    
    partLen = 64 - index; 
    
    //Transform as many times as possible.
    
    
    if (inputLen >= partLen)
        { 
        memcpy(&_buffer[index],input, partLen);
        _transform (&_buffer[0]); 
        
        for (i = partLen; i + 63 < inputLen; i += 64) 
            _transform (&input[i]); 
        
        index = 0; 
        } 
    else 
        i = 0; 
    
    /* Buffer remaining input */
    memcpy(&_buffer[index],&input[i],inputLen-i);
    
    }

void MD5::_finalize()
    {
     unsigned char bits[8]; 
     unsigned int index, padLen; 

       /* Save number of bits */
       encode (bits,_count, 8);

       /* Pad out to 56 mod 64.

*/
     index = (unsigned int)((_count[0] >> 3) & 0x3f); 
     padLen = (index < 56) ? (56 - index) : (120 - index); 
     _update (PADDING, padLen); 

       /* Append length (before padding) */
     _update (bits, 8);

       /* Store state in digest */
       //encode (digest, _state, 16);

       /* Zeroize sensitive information.

*/
     //MD5_memset ((POINTER)context, 0, sizeof (*context)); //we'll do in dtor
    _isFinalized=true;
    };

void MD5::_transform(const unsigned char *block)
    {
     unsigned a = _state[0], b = _state[1], c = _state[2], d = _state[3], x[16]; 

     decode (x, block, 64); 

       /* Round 1 */
       FF (a, b, c, d, x[ 0], S11, 0xd76aa478); /* 1 */
       FF (d, a, b, c, x[ 1], S12, 0xe8c7b756); /* 2 */
       FF (c, d, a, b, x[ 2], S13, 0x242070db); /* 3 */
       FF (b, c, d, a, x[ 3], S14, 0xc1bdceee); /* 4 */
       FF (a, b, c, d, x[ 4], S11, 0xf57c0faf); /* 5 */
       FF (d, a, b, c, x[ 5], S12, 0x4787c62a); /* 6 */
       FF (c, d, a, b, x[ 6], S13, 0xa8304613); /* 7 */
       FF (b, c, d, a, x[ 7], S14, 0xfd469501); /* 8 */
       FF (a, b, c, d, x[ 8], S11, 0x698098d8); /* 9 */
       FF (d, a, b, c, x[ 9], S12, 0x8b44f7af); /* 10 */
       FF (c, d, a, b, x[10], S13, 0xffff5bb1); /* 11 */
       FF (b, c, d, a, x[11], S14, 0x895cd7be); /* 12 */
       FF (a, b, c, d, x[12], S11, 0x6b901122); /* 13 */
       FF (d, a, b, c, x[13], S12, 0xfd987193); /* 14 */
       FF (c, d, a, b, x[14], S13, 0xa679438e); /* 15 */
       FF (b, c, d, a, x[15], S14, 0x49b40821); /* 16 */

      /* Round 2 */
       GG (a, b, c, d, x[ 1], S21, 0xf61e2562); /* 17 */
       GG (d, a, b, c, x[ 6], S22, 0xc040b340); /* 18 */
       GG (c, d, a, b, x[11], S23, 0x265e5a51); /* 19 */
       GG (b, c, d, a, x[ 0], S24, 0xe9b6c7aa); /* 20 */
       GG (a, b, c, d, x[ 5], S21, 0xd62f105d); /* 21 */
       GG (d, a, b, c, x[10], S22,  0x2441453); /* 22 */
       GG (c, d, a, b, x[15], S23, 0xd8a1e681); /* 23 */
       GG (b, c, d, a, x[ 4], S24, 0xe7d3fbc8); /* 24 */
       GG (a, b, c, d, x[ 9], S21, 0x21e1cde6); /* 25 */
       GG (d, a, b, c, x[14], S22, 0xc33707d6); /* 26 */
       GG (c, d, a, b, x[ 3], S23, 0xf4d50d87); /* 27 */



     GG (b, c, d, a, x[ 8], S24, 0x455a14ed); /* 28 */ 
     GG (a, b, c, d, x[13], S21, 0xa9e3e905); /* 29 */ 
     GG (d, a, b, c, x[ 2], S22, 0xfcefa3f8); /* 30 */ 
     GG (c, d, a, b, x[ 7], S23, 0x676f02d9); /* 31 */ 
     GG (b, c, d, a, x[12], S24, 0x8d2a4c8a); /* 32 */ 

       /* Round 3 */
       HH (a, b, c, d, x[ 5], S31, 0xfffa3942); /* 33 */
       HH (d, a, b, c, x[ 8], S32, 0x8771f681); /* 34 */
       HH (c, d, a, b, x[11], S33, 0x6d9d6122); /* 35 */
       HH (b, c, d, a, x[14], S34, 0xfde5380c); /* 36 */
       HH (a, b, c, d, x[ 1], S31, 0xa4beea44); /* 37 */
       HH (d, a, b, c, x[ 4], S32, 0x4bdecfa9); /* 38 */
       HH (c, d, a, b, x[ 7], S33, 0xf6bb4b60); /* 39 */
       HH (b, c, d, a, x[10], S34, 0xbebfbc70); /* 40 */
       HH (a, b, c, d, x[13], S31, 0x289b7ec6); /* 41 */
       HH (d, a, b, c, x[ 0], S32, 0xeaa127fa); /* 42 */
       HH (c, d, a, b, x[ 3], S33, 0xd4ef3085); /* 43 */
       HH (b, c, d, a, x[ 6], S34,  0x4881d05); /* 44 */
       HH (a, b, c, d, x[ 9], S31, 0xd9d4d039); /* 45 */
       HH (d, a, b, c, x[12], S32, 0xe6db99e5); /* 46 */
       HH (c, d, a, b, x[15], S33, 0x1fa27cf8); /* 47 */
       HH (b, c, d, a, x[ 2], S34, 0xc4ac5665); /* 48 */

       /* Round 4 */
       II (a, b, c, d, x[ 0], S41, 0xf4292244); /* 49 */
       II (d, a, b, c, x[ 7], S42, 0x432aff97); /* 50 */
       II (c, d, a, b, x[14], S43, 0xab9423a7); /* 51 */
       II (b, c, d, a, x[ 5], S44, 0xfc93a039); /* 52 */
       II (a, b, c, d, x[12], S41, 0x655b59c3); /* 53 */
       II (d, a, b, c, x[ 3], S42, 0x8f0ccc92); /* 54 */
       II (c, d, a, b, x[10], S43, 0xffeff47d); /* 55 */
       II (b, c, d, a, x[ 1], S44, 0x85845dd1); /* 56 */
       II (a, b, c, d, x[ 8], S41, 0x6fa87e4f); /* 57 */
       II (d, a, b, c, x[15], S42, 0xfe2ce6e0); /* 58 */
       II (c, d, a, b, x[ 6], S43, 0xa3014314); /* 59 */
       II (b, c, d, a, x[13], S44, 0x4e0811a1); /* 60 */
       II (a, b, c, d, x[ 4], S41, 0xf7537e82); /* 61 */
       II (d, a, b, c, x[11], S42, 0xbd3af235); /* 62 */
       II (c, d, a, b, x[ 2], S43, 0x2ad7d2bb); /* 63 */
       II (b, c, d, a, x[ 9], S44, 0xeb86d391); /* 64 */

     _state[0] += a; 
     _state[1] += b; 
     _state[2] += c; 
     _state[3] += d; 

       /* Zeroize sensitive information.



*/
     memset (x, 0, sizeof (x)); 
    }



MD5::operator unsigned() const
    {
    abkfatal(_isFinalized,"Can't read values from non-finalized MD5");
    return _state[0];
    }


MD5::operator MD5::Wrap128() const
    {
    abkfatal(_isFinalized,"Can't read values from non-finalized MD5");
    Wrap128 w128;
    w128.meat[0] = _state[0];
    w128.meat[1] = _state[1];
    w128.meat[2] = _state[2];
    w128.meat[3] = _state[3];
    return w128;
    }

MD5::~MD5()
    {
    //zeroize sensitive info
    memset(_state,0,16);
    }

unsigned MD5:: getWord(unsigned idx) const
    {
    abkassert(idx < 4, "Index out of range");
    return _state[idx];

    }


ostream& operator<<(ostream& os, const MD5& md5)
    {
    abkfatal(md5._isFinalized,"Can't output state of MD5 before finalization");
    int i;
    unsigned char digest[16];
    char buf[3];
    MD5::encode(&digest[0],md5._state,16);
    for (i=0;i<16;i++)
        {
        sprintf(buf,"%02x",digest[i]);
        os << buf;
        }
    return os;
    }

